Hidden gluten on food labels, names to look for
In short: Gluten is in wheat (including spelt, durum, semolina and khorasan), barley, rye and foods made from them, such as malt, bulgur, couscous and seitan. In the EU and UK the grain must be emphasised on the label; in the US only wheat is a major allergen. “Gluten-free” means no more than 20 mg/kg (20 ppm) in the EU and UK and below 20 ppm in the US.
Gluten is a protein found in wheat, barley and rye and in grains bred from them. For people with coeliac disease, even small amounts damage the gut, so the gluten-free diet has to be strict and lifelong. Wheat is easy to spot. Barley and rye often hide behind other names, especially on US labels.
How gluten appears on labels
- EU and UK: "cereals containing gluten" are one of the 14 allergens. The grain must be named and emphasised: "wheat flour", "barley malt extract", "rye". A label does not have to say "gluten" itself.
- US: only wheat is a major allergen. Barley, rye and oats are listed by name in the ingredients but are not flagged in the "Contains" line. A US product with "Contains: milk" can still contain barley malt.
Names that mean gluten
Wheat and its relatives:
- wheat, wheat flour, wholemeal, wheat starch (unless labelled gluten-free), wheat germ, wheat bran
- spelt, khorasan (Kamut), einkorn, emmer, durum, farro, freekeh
- semolina, farina, couscous, bulgur, graham flour, atta, seitan (wheat gluten)
- breadcrumbs, panko, croutons, rusk (in sausages), batter
- triticale (wheat-rye hybrid)
Barley and rye:
- barley, pearl barley, malt, malt extract, malt flavouring, malt syrup, malted milk
- brewer's yeast and most beer, lager, ale and stout (unless labelled gluten-free)
- rye, rye flour, pumpernickel
Often contains gluten (check the full list):
- soy sauce (usually brewed with wheat; tamari is often but not always wheat-free)
- gravy granules, stock cubes, soups and sauces thickened with flour
- seasoning mixes, crisps with malt vinegar flavour, coatings on chips and nuts
- liquorice, some sweets and chocolate bars with wafer or biscuit
- communion wafers, play dough (for children: allergies at school)
Ingredients that sound risky but are usually fine
These come from wheat or barley but are processed so heavily that the gluten is removed. EU law exempts some of them from allergen labelling, and coeliac organisations generally consider them suitable:
- glucose syrup, dextrose and maltodextrin, even from wheat
- distilled spirits such as whisky and vodka (distillation removes the protein)
- wheat starch in products labelled gluten-free (specially processed)
- barley malt vinegar in the small amounts used in food: Coeliac UK considers it acceptable, but check if you are unsure
Ingredients such as caramel colour (E150), modified starch and dextrin are only a problem if the label names wheat, barley or rye as the source. In the EU and UK this is required: "modified starch (wheat)".
What "gluten-free" means
| Claim | EU / UK | US |
|---|---|---|
| "Gluten-free" | max 20 mg/kg (20 ppm) | below 20 ppm |
| "Very low gluten" | max 100 mg/kg, only for foods made with specially processed cereals | not used |
| Oats | only if specially produced to avoid contamination, max 20 mg/kg | allowed if the whole food is below 20 ppm |
"Gluten-free" is voluntary. Many naturally gluten-free foods (rice, potatoes, plain meat) do not say it. Some products carry a certification mark, such as the Crossed Grain symbol licensed by Coeliac UK and other European coeliac societies, which involves independent audits.
"No gluten-containing ingredients" is a different claim used by some restaurants in the UK. It is not the same as "gluten-free" because cross-contamination may not be controlled. See eating out with coeliac disease.
"May contain gluten"
A "may contain wheat" or "made in a factory that handles gluten" line is voluntary and has no legal threshold. See what "may contain" means. Coeliac UK advises people with coeliac disease to avoid products with a "may contain gluten" warning. Products labelled gluten-free have been tested against the 20 ppm limit.
Coeliac disease, wheat allergy and gluten sensitivity
- Coeliac disease is an autoimmune condition. It is diagnosed with blood tests and usually a biopsy, while you are still eating gluten, so do not cut out gluten before testing.
- Wheat allergy is an immune reaction to wheat proteins. It can be immediate and severe, and people with it may tolerate barley and rye.
- Non-coeliac gluten sensitivity is a diagnosis made only after the other two have been ruled out.
Talk to your doctor before changing your diet. The NHS page on coeliac disease explains the tests.
How IngrediLens helps
With a gluten filter, IngrediLens highlights wheat, barley, rye and their other names (spelt, semolina, malt, seitan and many more). It also flags "may contain" gluten statements and "gluten-free" claims on the pack. It reads labels in English, Spanish, Portuguese, German, French and Italian, including terms like "sin TACC", "sem glúten", "glutenfrei", "sans gluten" and "senza glutine". The app does not certify any product, so check the pack and look for a trusted gluten-free mark.
Ingredient list allergen checker
Paste an ingredient list and see which of your allergens and “may contain” warnings it mentions.
Open the free toolCheck labels with IngrediLens
Point your iPhone camera at an ingredient list and IngrediLens highlights the allergens you chose and “may contain” statements. Free to start, no account, and your data stays on your device.
Download on the App StoreFrequently asked questions
What does "gluten-free" mean on a label?
In the EU, the UK and the US, "gluten-free" means the food contains less than 20 mg of gluten per kg (20 parts per million). In the EU and UK, "very low gluten" means no more than 100 mg/kg.
Is malt gluten-free?
No. Malt is usually made from barley, which contains gluten. Malt extract, malt flavouring and malted milk are not suitable on a gluten-free diet unless the product is labelled gluten-free.
Is glucose syrup made from wheat safe for coeliac disease?
Wheat-derived glucose syrup, dextrose and maltodextrin are so highly processed that they are exempt from EU allergen labelling. Coeliac UK considers them suitable for people with coeliac disease.
Are oats gluten-free?
Oats do not contain gluten in the same way wheat does, but standard oats are often contaminated with wheat or barley. Only oats sold as gluten-free are produced to avoid this. A small number of people with coeliac disease also react to pure oats, so ask your doctor or dietitian.
